Plasticity-induced repression of Irf6 underlies acquired resistance to cancer immunotherapy.

Acquired resistance to immune checkpoint immunotherapy remains a critical yet incompletely understood biological mechanism. Here, using a mouse model of pancreatic ductal adenocarcinoma (PDAC) to study tumor relapse following immunotherapy-induced responses, we found that tumors underwent an epithelial-to-mesenchymal transition (EMT) that resulted in reduced sensitivity to T cell-mediated killing. EMT-transcription factors (EMT-TFs) ZEB1 and SNAIL function as master genetic and epigenetic regulators of this tumor-intrinsic effect. Acquired resistance was not due to immunosuppression in the tumor immune microenvironment, disruptions in the antigen presentation machinery, or altered expression of immune checkpoints. Rather, EMT was associated with epigenetic and transcriptional silencing of interferon regulatory factor 6

Déclaration de conflit d'intérêts

Competing interests Dr. Stanger receives research funding from Boehringer-Ingelheim and previously served as a consultant to iTeos Therapeutics. Dr. Vonderheide reports receiving consulting fees from BMS, is an inventor on a licensed patents relating to cancer cellular immunotherapy and cancer vaccines and receives royalties from Children’s Hospital Boston for a licensed research-only monoclonal antibody.